<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>调用函数 this 改变</title>
</head>
<body>

    <input type="button" value="click me" onclick="demo()">
    
    <script>
        function demo () {
            console.log(this);
        }



        

    </script>
</body>
</html>